Rameshwar Dayal
Natural dyes were exclusively used for colouring till the middle of nineteenth century. But, due to accidental discovery of first synthetic dye mauveine by W.H. Perkin in1856, and a number of other synthetic dyes in latter part of nineteenth century, their use reduced considerably by the beginning of twentieth century. It was realized during the last decade of 20th century, that synthesis of dyes using aromatic chemicals and their subsequent use cause harmful ...